Research On Opportunistic Network Routing Strategy Based On Social Information Under Uncertain Relations

Opportunistic network originates from delay tolerant network(DTN),which is an ad-hoc network that can tolerate message delivery delay without end-to-end link between message source node and destination node.The nodes of opportunistic network meet other nodes by moving and establish short communication links to complete message forwarding.In the opportunistic network,encounters brought about by node movement lead to the formation of social relations,which are mainly determined by the specific interactions of nodes at the time of encounter and thus have uncertainty.Opportunistic network routing strategies based on social information between nodes in these uncertain social relations have become the focus of research on opportunistic message forwarding.This thesis studies two problems in existing routing strategies in uncertain social relations:1.The existing opportunistic network community division algorithms established based on social relations are insufficient in analyzing the encounters and communication between nodes,ignoring the influence of the interaction situation of nodes after meeting on messages forwarding.Moreover,the community division process does not target individual nodes,which makes the divided communities not have representative nodes.Therefore,this thesis proposes an opportunistic network routing strategy based on node private community division(NPCD).The strategy constructs private communities of nodes with social relations based on the social movement information between nodes,and helps to complete the forwarding of messages in the network.2.The existing opportunistic network routing algorithms cannot take into account both the delivery success rate and message security when routing messages.Therefore,this thesis proposes a hybrid opportunistic network security routing strategy based on node intimacy and trust value(NITV).The strategy constructs an inter-node intimacy mechanism and trust value mechanism according to the encounter situation of nodes and the successful forwarding records of messages.On this basis,the mixed utility value between nodes is calculated to decide whether messages are forwarded or not.The experimental results show that,compared with the classical routing strategies and the latest related routing strategies,the NPCD routing strategy and the NITV routing strategy proposed in this thesis have certain improvement in terms of the delivery success rate and the overhead ratio,and also reduce the number of relay nodes required for message delivery,which further reduce the probability of message loss and the probability of malicious nodes destroying messages.The adopted message copy control strategy reduces the number of message copies in the network,thereby reducing resource consumption in the network.